Re: NSA enhancing Linux security?

From: Christopher Browne (cbbrowne_at_acm.org)
Date: 02/29/04 

Date: 28 Feb 2004 23:04:56 GMT

Martha Stewart called it a Good Thing when Marc Schwartz <MSchwartz@mn.rr.com> wrote:
> Again, please...somebody verify my math.

The thing that would break your math would be if they had some fast
way of factoring public keys. The absence of such a thing is the
basis for RSA being considered "secure."

There is no straightforward way to prove that there is no fast way of
factoring the keys; if there was, we would probably know it by now.

And it's a hard sort of thing to prove; the converse is what would
likely be easy to prove. If you had a fast method to factor RSA keys,
then that would be the proof that RSA was insecure.

That's why PK using knapsack ciphers is considered insecure; a fast
method of cracking that was found.

It doesn't matter if your calculations are right or not; the point is
that they don't prove what you think they prove.

All they establish is that known brute-force attacks against RSA are
so slow that they are likely to be ineffective.

They don't prove the non-existence of some other "clever" attack that
does much better than brute force.

Finding "clever attacks" is what cryptanalysis is all about... 

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Relevant Pages

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